PRESIDENT Barack Obama has given a moving, eloquent, and determined speech to the mourning community of Newtown.

He says the weekend's tragedy - the fourth mass killing of his Presidency - shows America must change. They cannot tolerate any more mass killings. They must protect their children.

In what could be the first hint that he will try to tackle the US gun culture, he said he will do whatever is within his power to make the US a safer place.

'Are we prepared to say that such violence visited on our children year after year is somehow the price of our freedom?" he asked.

"These tragedies must end. And to end them, we must change."

And yet he failed to mention the word gun. Why? Because while pressure has been mounting for President Obama to take action on US gun culture since the weekend massacre, gun culture is much harder to change than you'd think.

Even if President Obama wanted to change the Second Amendment to control people's right to bear arms in the US, chances are he would fail.

The right to weaponry is enshrined in the US Constitution, which says:

A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

The Constitution is notoriously difficult to change – in part because it's revered, but also because technically it's a mammoth task, and one that usually fails. To change it:

* The amendment would have to pass the Senate with a two-thirds majority.

* It would also have to pass the House of Representatives with a two-thirds majority.

* Then it passes to state parliaments – and it has to pass three quarters of state parliaments.

This means that small, rural, gun-toting states can have the power to block any changes. There is a theoretical second way, which is to call a Constitutional Convention, but it's equally tricky and has never been attempted.

In 221 years, only 17 amendments have been ratified in the US apart from the Bill of Rights – and most of them were not as polarising as the gun debate.

Back in 2006, Mr Obama voted against amending the Constitution to prohibit the desecration of the Stars and Stripes, saying: "The Constitution should only be amended to address our nation's most pressing problems that can't be solved with legislation".

US political expert Dr Geoff Robinson, a lecturer at Deakin University, said he was pessimistic about the possibility of reform even if President Obama was willing. He says a Supreme Court Judge estimates as little as 2 per cent of the population could put an end to any amendments.

"It is so difficult to reform the US constitution. I'm doubtful (it will happen)," he said.

"I think that public opinion is horrified by this … but public support for gun control has gone down in the US because levels of violence crime have gone down.

Dr Robinson said the last significant proposed amendment to the Constitution was in the 70s, and it was to introduce equal rights for women – but that failed.

"That's the last time they even came close," he said.

"It just takes a few conservative states to block any proposal.

"I'd be doubtful if anything significant came out of this."

But there may be another way to at least reduce some types of available guns . In 1994, under then President Bill Clinton, there was a federal ban issued on military-style assault weapons. That ban expired in 2004 and hasn't been re-enacted yet, with conflicting reports over whether the ban worked to reduce crime.

Don De Bats, Professor of American Studies/Politics at Flinders University, said in the end it would be a matter for the states, not the Federal Government, to control guns - if that's what the people want.

"By and large this is an area of state legislation with limited federal control - although there are some areas of federal responsibility," he said.

"Obama may want to talk about what the federal government can do ... he can try to provide leadership on the issue."

And of course, any politician still has to face the fallout if they go against the will of the people on gun control.

Americans see it as their right. Sadly, after the shootings, there are reports of people lining up to buy guns - not necessarily because of impending changes to regulations, but just in time for Christmas.

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Comments on this story

Bazza of Australia Posted at 5:49 PM December 17, 2012

Over 90% of all weapons being used in mexico and the mexican cartel drug wars come from the united state. Drugs supply the US market. Guns supply the drug cartels. THe USA has over 100 fire arms companies chrning out military style assault weapons onto the streets of mexico and the US market. These weapons were not designed to hunt wild life or shoot small plastic targets at a shooting range. They were developed, refined and produced with the sole purpose of killing another human being. Period! I was in the army for 8 years and I can tell you that fire arms have no place in a civilized society. The NRA is too well financed and supported to be challenged. Unfortunatley until the USA as a nation decides to debate the issue and change the way it views weapons more massacres like this are on the way. We have not seen the last of mass murder in america.

Shane of the beach Posted at 5:49 PM December 17, 2012

Mature enough to know - Most of the guns that are used to kill people in Mexico originate in the USA.

Kaz of Vic Posted at 5:16 PM December 17, 2012

It is my understanding that 40% of guns in the US are purchased at gun shows where they 15 day wait and ID check is NOT enforced. Scary huh. I have no faith in human beings left...how can one imagine in their minds eye the horror, the fear that these babies felt when their tiny bodies were ripped apart and still go ahead and defend the sale, use and manufacture of guns along with the bizarre culture that surrounds them. It defies belief doesn't it?

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